Simple Method to Determine the Absolute Configuration of the Glycerol Moiety in Glycosyl Glycerols Based on ORD and CD

The reported enantioselective synthesis for the preparation of (+)-(2R,3R)-2-(4- hydroxy-3-methoxyphenyl)-3-hydroxymethyl-1,4-benzodioxane-6-carbaldehyde, precursor for the stereoselective synthesis of bioactive flavanolignans, could not be reproduced. Thus, the target molecule was prepared via the synthesis and separation of diastereomeric O-glucosides. TDDFT-ECD calculations and the 1,4-benzodioxane helicity rule were utilized to determine the absolute configuration. ECD calculations also confirmed that the 1Lb Cotton effect is governed by the helicity of the heteroring, while the higher-energy ECD transitions reflect mainly the orientation of the equatorial C-2 aryl group.

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Absolute configuration at C(20) of the derivatives of 21-nor-5α-cholane-20,24-diol

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19802443 ◽

1980 ◽

Vol 45 (9) ◽

pp. 2443-2451

Author(s):

Vladimír Pouzar ◽

Miroslav Havel

Keyword(s):

Absolute Configuration ◽

Side Chain ◽

Chemical Correlation ◽

The Absolute ◽

Derivatives Of

Derivatives of 21-nor-5α-cholane-20,24-diol XI and XIX were prepared by stepwise construction of the side-chain in the position 17β. Their absolute configuration at C(20) was determined on the basis of chemical correlation with the derivatives of 21-nor-5α-cholan-20-ol, XVI and XXIV. The absolute configuration of alcohols XVI and XXIV was determined from the ratio of the yields in which they are formed during the reduction of ketone X and using the benzoate rule. To compounds XI-XVIII the configuration 20R and to compounds XIX-XXVI the configuration 20S has been assigned.

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Absolute Stereochemistry of (-)-Wieland-Miescher Ketone as Established by the X-ray Crystallographic and CD Exciton Chirality Methods

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19921459 ◽

1992 ◽

Vol 57 (7) ◽

pp. 1459-1465 ◽

Cited By ~ 4

Author(s):

Nobuyuki Harada ◽

Tatsuo Sugioka ◽

Hisashi Uda ◽

Takeo Kuriki

Keyword(s):

Structure Analysis ◽

Absolute Configuration ◽

X Ray ◽

The Absolute ◽

Absolute Stereochemistry

The 8aR absolute stereochemistry of Wieland-Miescher ketone (-)-I was established by the X-ray structure analysis of its bis(4-bromobenzoate) derivatives (1R,6R,8aR)-(+)-IV and (1R,6S,8aR)-(-)-V. The absolute configuration of (-)-I was corroborated further by the application of the CD exciton chirality method to bis(4-bromobenzoates) (+)-IV and (-)-V.

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Rapid Organocatalytic Chirality Analysis of Amines, Amino Acids, Alcohols, Amino Alcohols and Diols with Achiral Iso(thio)cyanate Probes

Chemical Science ◽

10.1039/d1sc02061g ◽

2021 ◽

Author(s):

Eryn Nelson ◽

Jeffrey S. S. K. Formen ◽

Christian Wolf

Keyword(s):

Amino Acids ◽

Absolute Configuration ◽

Rapid Determination ◽

Amino Alcohols ◽

Enantioselective Synthesis ◽

Widespread Occurrence ◽

Chiral Compounds ◽

New Methods ◽

The Absolute

The widespread occurrence and significance of chiral compounds does not only require new methods for their enantioselective synthesis but also efficient tools that allow rapid determination of the absolute configuration,...

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